<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    
</head>
<body>
    <div id="header" style="border: 1px solid red;">
        <h1>xxx code</h1>
    </div>
    <!-- 头部 -->
    <div id="content" style="border: 1px solid blue;height: 780px;">
        aa
    </div>
    <!--主体  -->
    <div id="foot" style="border: 1px solid green;">
        bb
    </div>
    <!-- 页脚 -->
    
</body>
</html>